Predicting natural arsenic enrichment in peat-bearing, alluvial and coastal depositional systems: A generalized model based on sequence stratigraphy.

Hazardously high concentrations of arsenic exceeding the threshold limits for soils and drinking waters have been widely reported from Quaternary sedimentary successions and shallow aquifers of alluvial and coastal lowlands worldwide, raising public health concerns due to potential human exposure to arsenic. A combined sedimentological and geochemical analysis of subsurface deposits, 2.5-50 m deep, from the SE Po Plain (Italy) documents a systematic tendency for naturally-occurring arsenic to accumulate in peat-rich layers, with concentrations invariably greater than maximum permissible levels. A total of 366 bulk sediment samples from 40 cores that penetrated peat-bearing deposits were analysed by X-ray fluorescence. Arsenic concentrations associated with 7 peat-free lithofacies associations (fluvial-channel, levee/crevasse, floodplain, swamp, lagoon/bay, beach-barrier, and offshore/prodelta) exhibit background values invariably below threshold levels (<20 mg/kg). In contrast, total arsenic contents from peaty clay and peat showed 2-6 times larger As accumulation. A total of 204 near-surface (0-2.5 m) samples from modern alluvial and coastal depositional environments exhibit the same trends as their deeper counterparts, total arsenic peaking at peat horizons above the threshold values for contaminated soils. The arsenic-bearing, peat-rich Quaternary successions of the Po Plain accumulated under persisting reducing conditions in wetlands of backstepping estuarine and prograding deltaic depositional environments during the Early-Middle Holocene sea-level rise and subsequent stillstand. Contamination of the Holocene and underlying Pleistocene aquifer systems likely occurred through the release of As by microbially-mediated reductive dissolution. Using high-resolution sequence-stratigraphic concepts, we document that the Late Pleistocene-Holocene lithofacies architecture dictates the subsurface distribution of As. The "wetland trajectory", i.e. the path taken by the landward/seaward shift of peat-rich depositional environments during the Holocene, may help predict spatial patterns of natural As distribution, delineating the highest As-hazard zones and providing a realistic view of aquifer contamination even in unknown areas.

Translating knowledge into policy: Organizational model and minimum requirements for the implementation of a regional pancreas unit network.

Pancreatic and periampullary cancers pose significant challenges in oncological care due to their complexity and diagnostic difficulties. Global experiences underscore the crucial role of multidisciplinary collaboration and centralized care in improving patient outcomes in this context. Recognizing these challenges, Lombardy, Italy's most populous region, embarked on establishing pancreas units across its territory to enhance clinical outcomes and organizational efficiency. This initiative, driven by a multistakeholder approach involving the Lombardy Welfare Directorate, clinicians, and a patient association, emphasizes the centralization of complex care in high-volume hospitals, adopting a hub-and-spoke model and a multidisciplinary approach. This article outlines the process and criteria set forth for pancreas unit implementation, aiming to provide a structured framework for enhancing pancreatic cancer care. Central to this initiative is the establishment of structured criteria and minimal requirements, not only for surgery but also for other essential components of care, ensuring a comprehensive approach to pancreatic cancer management. The Lombardy model offers a structured framework for enhancing pancreatic cancer care, with potential applicability to other regions and countries seeking to improve their cancer care infrastructure.